The fire on Clavelita Street near Del Sur Boulevard broke out for unknown reasons shortly after 12:30 a.m., according to the San Diego Fire-Rescue Department. The dwelling that caught fire was the smaller of two homes on the property.
The man living in the main house on the property awoke to the screaming of his disabled brother, who lives in the smaller home. He rushed to his brother's aid and pulled him to safety from the burning house.
The disabled man was taken to a hospital, but his condition was not known, fire officials said.
The cause of the fire was not immediately determined, a city fire dispatcher said.